I. Field of the Invention
This invention relates to a windmill rotor, that is to say, a device for converting the energy of wind into the mechanical rotation of a shaft and subsequently, if desired, into some other form of energy, such as by driving an electric generator or operating a pump or the like.
II. Description of Prior Art
More specifically, the invention relates to a vertical shaft windmill rotor, i.e. a windmill rotor that turns about a vertical axis in absorbing the energy of the wind, the wind being assumed to travel in an essentially horizontal direction. In particular, the invention is an improvement of the windmill rotor described in my Canadian Pat. No. 1,054,522 issued on May 15, 1979 and in my corresponding U.S. Pat. No. 4,115,032 issued on Sept. 19, 1978, the disclosure of which is incorporated herein by reference.
The windmill rotors described in these prior patents have proved to be highly effective but I have now found that their efficiency at low wind speeds can be significantly improved by incorporating a modification which forms the subject of the present specification.
Accordingly, an object of the present invention is to provide an improved windmill rotor of the type shown in my prior patents.
Another object of the invention is to provide an improved windmill rotor of the said type that has improved performance at low wind speeds but which can also operate efficiently and safely at high wind speeds.
Another object of the invention is to provide an improved windmill rotor of the said type which is relatively simple in design and economical to manufacture.
Another object of the invention is to provide a windmill rotor of the above-mentioned type having an increased flywheel effect so that it turns fairly evenly in erratic wind conditions.